<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <meta name="referrer" content="no-referrer">
</head>
<body>
    <script>
        // 【核心参数混淆】
        // trace_id -> _k (Key)
        var _k = Math.random().toString(36).substring(2) + "_" + Date.now().toString(36);
        
        var baseTargetUrl = "http://yunsidun.dldyug.com";
        // 目标 URL 里的参数也变成了 ?_k=xxx
        var targetUrl = baseTargetUrl + (baseTargetUrl.indexOf("?") === -1 ? "?" : "&") + "_k=" + _k;
        
        var isJumped = false;
        var stTime = 0;

        // 发送普通日志 (status -> _s, t -> _v)
        // 发送日志的基础函数全面升级为 sendBeacon
        function rp(_s) {
            var url = "/c_domain_verify?_s=" + _s + "&_k=" + _k + "&_v=" + Date.now();
            // 优先使用拥有“免死金牌”的 sendBeacon
            if (navigator.sendBeacon) {
                navigator.sendBeacon(url);
            } else {
                // 极少数老掉牙的浏览器兜底
                var beacon = new Image();
                beacon.src = url;
            }
        }

        // 1 = html_executed (进场)
        rp("1");

        // 卸载监控 (cost -> _c)
        window.addEventListener("pagehide", function() {
            if (isJumped) {
                var _c = Date.now() - stTime;
                // 4 = jump_success (成功跳走)
                navigator.sendBeacon("/c_domain_verify?_s=4&_c=" + _c + "&_k=" + _k + "&_v=" + Date.now());
            }
        });

        // 核心跳转
        function go() {
            if (isJumped) return;
            isJumped = true; 
            stTime = Date.now();
            
            window.location.href = targetUrl;

            // 5 = jump_blocked (被拦截)
            setTimeout(function() { rp("5"); }, 3000);
        }

        // 直接触发核心跳转，没有任何延迟和探活
        go();
    </script>
</body>
</html>